Dehumidifier System Device and Method

ABSTRACT

A dehumidifier system and device for maintaining a dry air environment in enclosures by extracting the water to outside the enclosure. The dehumidifier device comprises a condensation unit, typically a thermoelectric clement with a moisture collector, and a sealed pump, such as peristaltic pump, which pumps the condensed humidity out of the sealed enclosure, yet maintains the enclosure seal. The system is provided with a controller which alternately activates the thermoelectric element and the pump, in at least one mode: continuous, periodical, and programmable utilizing a humidity/relative humidity sensor. Optionally, in large-volume enclosures and containers, a fan assembly is connected to the controller so as to provide for rapid circulation of the air and removal of moisture.

FIELD OF THE INVENTION

The present invention relates generally to dehumidifier systems anddevices, and more particularly to a dehumidifier system device andmethod for active water extraction from small enclosures and containersto a space external thereto.

BACKGROUND OF THE INVENTION

Dehumidifier systems and devices are in widespread use today, especiallyin buildings, storage centers, and other sites where active central-airconditioning systems are installed. Gas-heated systems are also commonin homes and offices and in places where the undesirable effect of thedrying of the heated air results in loss of beneficial levels ofhumidity needed for good health. Most such devices and systems are largeand thus not well-suited for dehumidification of small enclosures andcontainers.

For these latter applications, a passive system is generally employedutilizing chemicals in powder or gel form, such as silica-gel or otherhydrophobic materials which are introduced to absorb undesirablemoisture. Applications include small, closed containers for storing,shipping, or displaying tobacco products, electronic components, and thelike. In some applications, nitrogen or some other dry gas is introducedunder low pressure into a container so as to displace the naturallyhumid air of the atmosphere. The presence of pressurized gas is intendedto prevent the reentry of the surrounding air.

There are several problems with the above-mentioned devices and systems.One is that the moisture-laden air extracted from a defined, treatedspace is frequently not exhausted external to the closed system andtherefore there exists the potential for such moisture-laden air torecycle and return to the treated space.

Another problem is that nitrogen filled containers which are pressurizedrequire a high level of closure and this generally involves additionalexpense, such as providing. specially shaped gaskets, tight-fittingcovers, and the like. Furthermore, in some applications, such as opticalsystems, pressure is not always a positive factor. Furthermore,pressurized systems require a modicum of maintenance, which adds to thecost of using such systems for protection against humidity and moisture.

Thus there is a need for a dehumidifier system which actively extractswater moisture from small enclosures and containers to a space externalthereto; which does not require the introduction of pressurized drygases and the related expense of providing a high level of closure forsuch an application; and which reduces the need for an inordinate amountof maintenance.

SUMMARY OF THE INVENTION

Accordingly, it is a principal object of the present invention toovercome the disadvantages of prior art dehumidifier systems, andprovide a dehumidifier system and device for maintaining a dry airenvironment in enclosures, by extracting the water to outside theenclosure.

In accordance with a preferred embodiment of the present invention,there is provided a dehumidifier device for removing condensed humidityout of a sealed enclosure, said dehumidifier device comprising:

a controller;

a condenser unit, having a thermoelectric element in close proximity toa moisture collector; and

a sealed pump unit comprising:

-   -   a pump mounted in a housing, and    -   a hose for directing moisture external to said sealed enclosure,        wherein when said controller operates said condenser unit and        said sealed pump unit, collected moisture is pumped out of said        sealed enclosure through said hose.

The dehumidifier device of the present invention comprises acondensation unit, typically a thermoelectric element with a moisturecollector, and a sealed pump, such as peristaltic pump, which pumps thecondensed humidity out of the sealed enclosure, yet maintains theenclosure sealing. The system is provided with a controller whichalternately activates the thermoelectric element and the pump, eithercontinuously, periodically, or in accordance with a humidity or relativehumidity sensor. Optionally, in large-volume enclosures and containers,a fan assembly is connected to the controller so as to provide for moreefficient circulation of the air since it is desirable to have a morerapid removal of moisture.

The device is particularly useful in keeping a dry environment inenclosures where humidity can damage such items as electronic devicesand components, food, mechanical systems; or where humidity can fog aviewing window, such as in outdoor displays. While the commonly usedexisting solution of applying a silica-gel inside the enclosure issimple and of relatively low-cost, it cannot provide a solution forlonger periods, since the silica-gel has limited capacity and needs tobe dried before it can be re-used. The dehumidifier device describedherein has an unlimited capacity, and thus can provide a dry environmentsolution for long periods, as well as overcome imperfect sealing.

The invention is also shown in an embodiment having a vaporizing heaterunit provided on the exhaust side of the condenser unit for vaporizingany moisture exhausted from the system and preventing unwanted, andperhaps damaging water leaks resulting from the action of thedehumidifier.

Additional features and advantages of the invention will become apparentfrom the following drawings and description.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention with regard to theembodiments thereof, reference is made to the accompanying drawings, inwhich like numerals designate corresponding elements or sectionsthroughout, and in which:

FIG. 1A is a general, cross-section view of the system of the inventionin accordance with a preferred embodiment thereof;

FIG. 1B is an enlarged, detailed view of the invention from FIG. 1A;

FIG. 2 is an enlarged, detailed, cross-section view of the arrangementof the condenser unit and funnel components of the invention from FIG.1; and

FIG. 3 is a perspective view of another embodiment of the inventionshowing a heater unit mounted in proximity to the exhaust hose.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

FIG. 1A is a general, cross-section view of the system of the inventionin accordance with a preferred embodiment thereof. FIG. 1A shows anenclosure 10 where it is desired to maintain a dry environment andindicates a view B of the device of the invention internally mounted inenclosure 10.

FIG. 1B is an enlarged, detailed view of the invention from FIG. 1A.

In a preferred embodiment of the invention, the dehumidifier systemcomprises a fan assembly 12, having a propeller 14 mounted inside apropeller housing 16, a condenser unit 18, a pump unit 20, and a pumphousing 22. Condenser unit 18 comprises a thermoelectric element 24provided with a central moisture collector 26 (indicated with hatchlines) formed with a funnel 28. Collector 26 and funnel 28 are typicallymade of stainless steel. Collector 26 is attached to thermoelectricelement 24 utilizing a heat-conducting grease. An isolator hub 30),positioned in close proximity to collector 26, isolates the cold surfaceof thermoelectric element 24 from pump housing 22. Pump unit 20, in apreferred embodiment of the invention, is a sealed liquid pump that canmove moisture out, but prevents air from getting into enclosure 10 so asto maintain the integrity of the sealed enclosure.

In another embodiment of the invention, the moisture is condensed andturned directly into ice formed on the cold face of thermoelectricelement 24, cooled when when in the cooling mode resulting fromapplication of the Peltier effect. This embodiment makes a simpler andless expensive device as it does not require a condenser unit 18, afunnel 28, nor application of grease. For example, if the cold face isvertical and the ice is melts, hose 34 is disposed in such a way as tocatch the water formed from the ice which falls by gravity directly intothe opening of hose 34.

FIG. 1 shows a peristaltic-type pump assembly 20, by way of example,which moves a liquid down a flexible hose 34, by rotating a two-wheel,rollers element 32 which presses hose 34 connected to the bottom portionof funnel 28, and penetrates enclosure 10 through an air-tight seal (notvisible) exiting at exhaust 38 to the outside environment. A controller36 comprises an electronic circuit, which controls fan assembly 12,thermoelectric element 24, and pump unit 20, either continuously,periodically, or in accordance with humidity/relative humidity sensors(not shown).

When fan assembly 12 is activated, it blows air on condenser unit 18.Thermoelectric element 24 cools down moisture collector 26 throughisolator hub 30 disposed above thermoelectric element 24, keeping thebottom plate 31 at room temperature due to pump housing 22 whichfunctions as a heat sink. The humid air blowing on the upper portion ofmoisture collector 26 is cooled, thus condensing water from enclosure 10and forming moisture on moisture collector 26. By capillary action, thewater drops are drawn down into the central hole in moisture collector26, and are caught below isolator hub 30, where they are directed toenter peristaltic hose 34. Pump unit 20 then pushes the water dropsfurther down peristaltic hose 34 until they are extracted outsideenclosure 10 through exhaust 38.

Alternatively, instead of collecting the moisture as it drops, it isfrozen to form ice which builds up on a surface of thermoelectricelement 24 when the surface is cooled to form a cold face by the Peltiereffect. The depth of ice build-up is regulated to about 1 mm inthickness and then heated by changing the polarity of thermoelectricelement 24. This turns the ice back into water which falls by gravityinto the pump inlet of hose 34.

A numerical example of how the dehumidifier device works is describedbelow: assuming an enclosure of 1 liter, filled with air at 20° C., 70%relative humidity. The absolute amount of water in the air is 70% thesaturated vapor amount the air can hold at this temperature is 70%×17mGram=12 mGram. Thermoelectric element 24 is then cooled to −10° C.,where the saturated vapor amount the air can hold is only 2.3 mGram, sowater drops up to 10 mGrams (10 mm³) in size will be condensed and flowdown funnel 28 into peristaltic hose 34 pumped by pump unit 20, pushingthe water drops out of enclosure 10, and leaving a potential relativehumidity of 2.3/17=13%.

Pump unit 20 can be operated as soon as, and as long as humidity issensed between moisture collector 26 and isolator hub 30. Such sensingcan be obtained, for example, by measuring the resistance betweencollector 26 and isolator hub 30, the bottom side of isolator hub 30being provided with a conductive coating.

In another embodiment of the invention, to eliminate getting anunder-pressure inside enclosure 10 due to the operation of pump unit 20,another hose (not shown) is provided which returns outside air toenclosure 10 in the same volume as the water pumped out. Alternatively,a regulating valve (not shown) is added to enclosure 10, which opens ifthe inside pressure drops below a certain threshold.

In an alternative embodiment of the invention, the whole dehumidifierdevice is minimized in dimension to the size of a small chip where theperistaltic pump unit 20 is replaced with, for example, a piezo-basedmicro-pump such as one commonly used in inkjet printers. Fan assembly 12need not necessarily be disposed as part of the dehumidifier device andcan be situated at any other place within the enclosure being treated.

FIG. 2 is an enlarged, detailed, cross-section view of the arrangementof the condenser unit and funnel components of the invention from FIG.1.

In particular, condenser unit 18 is shown in close proximity tocollector 26 nestled in the upper surface of isolator hub 30. A portionof rollers element 32 is also shown in a cut-away view of peristaltichose 34. Thermoelectric element 24 is sandwiched between isolator hub 30and bottom plate 31. Funnel 28 is fitted snugly to moisture collector 26directing water drops collected by collector 26 into hose 34.

FIG. 3 is a perspective view of another embodiment of the inventionshowing a vaporizing heater unit mounted on the exhaust side of thecondenser unit. In operation, fan assembly 12 rotates propellers 14inside their housing 16 shown in a cut-away view. The cool air(indicated by broad curving arrows) condenses any moisture withinenclosure 10 onto condenser unit 18. The water drops indicated by theflowing arrows inside peristaltic hose 34 are pumped through theelements of a heater unit 40 disposed at exhaust 38 converting the waterdrops into steam which can easily be passed to the outside air todisperse.

In prior art systems the water exiting a dehumidifier is conveyed to awater collector or discharged through a small diameter tube, or, forsmall quantities of water, simply leaked out onto a floor or desk. Thepresent invention, in the embodiment shown in FIG. 3, is advantageouslyprovided with a heating unit mounted in the exhaust, outlet, which turnscondensed water exiting the system into steam. The steam is thenvaporized and released to mix with the outside air.

Yet another option is to spread the water out into the air by means of ablower, for example, which disperses miniature drops of water into theair in a manner similar to some types of air coolers. Another option isto spread the water out into the air by using an ultrasonic vaporizer.

Having described the present invention with regard to certain specificembodiments thereof, it is to be understood that the description is notmeant as a limitation, since further modifications may now suggestthemselves to those skilled in the art, and it is intended to cover suchmodifications as fall within the scope of the appended claims.

1. A dehumidifier device for removing condensed humidity out of a sealedenclosure, said dehumidifier device comprising: a controller; acondenser unit, having a thermoelectric element in close proximity to amoisture collector; and a sealed pump unit comprising: a pump mounted ina housing, and a hose for directing moisture external to said sealedenclosure, wherein when said controller operates said condenser unit andsaid sealed pump unit, collected moisture is pumped out of said sealedenclosure through said hose.
 2. The dehumidifier device of claim 1further provided with at least one means for exhausting moisture outinto the atmosphere selected from the group comprising: a vaporizingheater unit provided on the exhaust side of said condenser unit forvaporizing condensed water exiting said sealed enclosure; a blower tospread the condensed water out into the air in miniature drops; and anultrasonic vaporizer.
 3. The dehumidifier device of claim 1 furtherprovided with a fan assembly connected to said controller so as toprovide for rapid circulation of the air and removal of moisture inlarger volume enclosures.
 4. The dehumidifier device of claim 1 whereinsaid controller comprises an electronic circuit.
 5. The dehumidifierdevice of claim 1 wherein said pump is provided with a one-way valve toprevent back-flow into said sealed enclosure.
 6. The dehumidifier deviceof claim 1 wherein said pump is a peristaltic-type, liquid pump.
 7. Thedehumidifier device of claim 1 wherein said pump is a piezo-basedmicro-pump.
 8. The dehumidifier device of claim 1 wherein saidcontroller is connected to said thermoelectric element and said sealedpump unit so as to provide alternating cycles of activation anddeactivation of said thermoelectric element and said sealed pump unit toproduce a Peltier effect, alternatively heating and cooling saidcondenser unit.
 9. The dehumidifier device of claim 8 wherein saidcondenser unit is oriented so as provide a cold face directly exposed toair flow when alternatively cooled by said Peltier effect.
 10. Thedehumidifier device of claim 8 wherein said cold face is cooled to atemperature less than zero degrees Celsius so that moisture contactingsaid cold face immediately turns into ice.
 11. The dehumidifier deviceof claim 8 wherein said cold face is periodically heated by changing thepolarity of the Peltier effect applied to said thermoelectric element sothat the ice on said cold face is melted and the resulting water isexhausted from said dehumidifier device.
 12. The dehumidifier device ofclaim 8, wherein said alternating cycles of activation and deactivationcomprise at least one of the operating modes selected from the group:continuous; periodical; and programmable.
 13. The dehumidifier device ofclaim 12 wherein said programmable operating mode is a function providedby a humidity/relative humidity sensor.
 14. The dehumidifier device ofclaim 1 further comprising a second hose which returns outside air tosaid sealed enclosure in the same quantity as water pumped out therefromto eliminate getting an under-pressure inside said sealed enclosure dueto the operation of said pump unit.
 15. A dehumidifier system forremoving condensed moisture from humidity out of a sealed enclosurecomprising: a controller for operating said system; a condenser unit,having a thermoelectric element in close proximity to a moisturecollector; and a sealed pump unit comprising: a pump mounted in ahousing, and a hose for directing moisture external to said sealedenclosure, wherein when said controller operates said condenser unit inconjunction with said sealed pump unit, moisture is collected and pumpedthrough said hose external to said sealed enclosure.
 16. A method fordehumidifying air and removing moisture from a sealed enclosure, saidmethod comprising the steps of: providing a condenser unit having athermoelectric element in close proximity to a moisture collector;providing a sealed pump unit comprising: a pump mounted in a housing,and a hose for directing moisture external to said sealed enclosure,providing a controller in communication with said condenser unit andsaid pump unit, wherein when said controller is activated, saidcondenser unit extracts moisture from said sealed enclosure and saidpump pumps said moisture external to said sealed enclosure via saidhose.
 17. The method of claim 16 further comprising the steps of:connecting said controller to said thermoelectric element and saidsealed pump unit so as to provide alternating cycles of activation anddeactivation of said thermoelectric element and said sealed pump unit toproduce a Peltier effect, alternatively heating and cooling saidcondenser unit; orienting said condenser unit so as provide a cold facedirectly exposed to air flow when alternatively cooled by said Peltiereffect; cooling said cold face to a temperature less than zero degreesCelsius so that moisture contacting said cold face immediately turnsinto ice; and heating said cold face periodically by changing thepolarity of the Peltier effect applied to said thermoelectric element sothat the ice on said cold face is melted and the resulting water isexhausted from said dehumidifier device.
 18. The method of claim 16wherein said controller alternately activates said thermoelectricelement and said pump in at least one of the modes selected from thegroup: continuous; periodical; and programmable.
 19. The method of claim17 wherein said programmable operating mode is a function provided by ahumidity/relative humidity sensor.
 20. The method of claim 16 furthercomprising: vaporizing condensed water exiting said sealed enclosure;and promoting rapid circulation of the air and removal of moisture inlarge-volume enclosures.